Borussia Dortmund coach Jurgen Klopp has warned his side that they will need to be patient against rivals Schalke in the keenly awaited Revierderby on Saturday.
Dortmund, who have won three Bundesliga games in a row for the first time in what has been a troubled season, hope to maintain their momentum in the home clash against their local rivals.
Klopp praised Schalke, who have become harder to beat under former Chelsea boss Roberto Di Matteo, calling them a "result machine."
"They are very stable at the back," he told his prematch news conference on Thursday. "They wait for the counter-attack, and they will not change that against us.
"It's clear how they play -- and you usually don't know that 100 percent.
"Against a team that defends relatively deep with eight men, you will not get chance every second. We need to convert possession into chances."
Since taking over in mid-October, Di Matteo has introduced a 5-3-2 system that has made Schalke more resilient but seen them score only four goals in the five games since the Bundesliga's winter break.
They are set to welcome back Netherlands attacker Klaas-Jan Huntelaar after suspension, while right-back Atsuto Uchida could also return.
But Di Matteo ruled out any change between the posts, where 19-year-old Timon Wellenreuther continues to deputise for the injured Ralf Fahrmann.
"I am absolutely satisified with Timon. He has done really well so far," the coach told a news conference.
"He has played better than we all hoped he would, even though he is a young lad and does not have the experience of a Ralf Fahrmann."
Neither Fahrmann nor his deputy, Fabian Giefer, are expected back in the squad within the next two weeks.
